Polyurethane foams from polyesters of epoxy acids



3,184,420 Ce Patented May 18, T1965 United States Patent occurs at room temperature spontaneously and follows 3,18 several courses concurrently and consecutively. The hy- POLYURETHANE FOAMS FROM POLYESTERS droxyl groups of the polymeric ester react with the poly- OF EPOXY ACIDS isocyanate to give polymer chain lengthening and chess- Karl Brack, Wilmington, Del., assignor to Hercules linking by formation of urethane groups. If water is 53:35: 5 ompany wflmmgton a corporation of the blowing agent, the polyisocyanate reacts with it to No Drawing. Filed 23 9 2 Sen 247,843 give an amine and carbon dioxide gas (which blows the I ,8 Claims. (Cl. 260-25) cellular structure). The amine further reacts with more isocyanate to give urea groups. The urea groups will This invention relates to polyurethane foams and to also react with isocyanate to give biuret groups. If a low their preparation. More particularly, the invention reboiling liquid, e.g., trich'lorofluoromethane, is the blowlates to polyurethane foams prepared from linear polying agent, the cellular structure is attained through vapormeric esters and polyisocyanates. ization of this liquid by the heat of reaction.

It is known in the art to prepare polyurethanes from The polymeric esters employed in accordance with the polyols and isocyanates. The reaction can be shown as 5 instant invention are linear polyesters having a plurality follows: of OH substituent groups attached at regular intervals H along the polymer chain and which may or may not be terminated with epiha'lohydrin or alkylene oxide end groups The preparation of the linear polymeric esters p and end termination is fully described in my copending The polymers take their name from the urethane link- Parfim Pawnt pp Serial 141,020, filed pages f d Depending on the nature f the reactants tember 27, 1961. As stated therein, the polymeric esters and the process used, the resulting polymer can take one are P p y heating either an BPOXidiZed aliphatic f several f such as foams, Synthetic rubbers, acid or a halohydrated saturated aliphatic acid or mixture hesives, coatings, fibers, molding compounds, etc. Even e f Wlth P l a basic catalyst- The Simplest in the relatively narrow field of polyurethane foams, epoxldlled ahphatlc acld is P YP P acid,

there are a large number of known reactants and proc- 0 esses. The polyols known in the prior art can be eml ployed in one or two of the conventional methods for preparing foams but no single polyol has been found with O universal applicability, i.e., none of the prior art polyols Other typical epoxidized saturated aliphatic acids include can be used in all of the methods for the preparation of by way of example, 2,3-epoxybutyric acid; 3,4-epoxybupolyurethane foams. For example, it has not been possityric acid; 2,3 epoxyhexanoic acid; 3,4 epoxyhexanoic ble in the past to prepare polyurethane foams from ester polyols by the least expensive process, i. e., the so-called one-shot method. In addition, the polyurethane foams undecanoic acid; 5,6-epoxyundecanoic acid; 10,11-epoxyof the prior art;su1fer from shrinkage and are not resistant unde'canoic acid; 2,3-epoxyhexadecanoic acid; 7,8-epoxyto humid aging. hexadecanoic acid; 15,16 epoxyhexadecan-oic acid; 2,3-

epoxyoctadecanoic acid; 9,10 epoxyoctadecanoic acid; 10,11 epoxyoctadenoic acid; 11,12 epoxyoctademnoic It has now been discovered that certain linear polymeric esters can be used in the preparation of polyurethane foams by all of the conventional methods and particuacid; 12,13-epoxyoctadecanoic acid; l7,l8-epoxyoctadeclarly for the preparation of rigid urethane foams by the anoic acid, and the like. Typical halohydrated saturated one-shot process. The resulting foams are free from aliphatic acids include by way of example, 2(3)'-chloroshrinkage and are resistant to humid aging. 3(2)-hydroxybutyric acid; 3(4) bromo 4(3) hydroxy- Accordingly, the present invention relates to poly- 4 butyric acid; 2(3)-iodo-3(2)-hydroxyhexanoic acid; 3(4)- urethane foams comprising the foamed reaction product chloro-4(3) -hydroxyhexanoic acid; 5(6) chloro- 6(5)- of an organic polyisocyanate and a polyol containing at hydroxyoctanoic acid; 7 (8)-bromo-8(7)-hydroxyoctanoic least 10%, most preferably 25%, by weight of a linear acid; 2(3)-chloro-3(2)-hydroxyhexadecanoic acid; 7(8)- polymeric ester having the general formula: iodo 8(7) hydroxyhexadecanoic acid; 15 (16) chloro- L-cnl J 11-] in which R is a substituent of the group consisting of 16(15) -hydroxyhexadecanoic'acid; 2(3) -chloro-3(2)- hydrogen and alkyl radicals; n is a whole number from hydroxyoctadecanoic acid; -9(10)-chl-oro-10(9)-hydroxy- 0 to 20, inclusive; x is at least 1; W is a substituent of the octadecanoic acid; 10(11)-chloro 11(10) hydroxyoctagroup consisting of hydrogen, hydroxyalkyl radicals and decanoic acid; 11(12)-chloro- 12(11) -hydroxyoctadecahalohydroxyalkyl radicals; and B is a substituent of the 0 n0 ac d; 12(13)-chloro-13(12)-hydroxyoctadecan-oic group consisting of acid; 17(1 8)-bromo 18(17) hydroxyoctadecanoic acid; R-CI-ICH-radlcals, RC1I-CH-ra lieals,nud RCHCII-radicals and f i Tilose ,Polymem esters Prepared from epoxldized aliphatic acids such as 9,10-epoxystearic acid 0 X H H X are most preferred. If end termination is desired, a chain in which R has the same significance as set forth above terminator (epihalohydrin or alkylene oxide) can be and X is a substituent of the group consisting of halogen added during the polymerization. radicals and acyloxy radicals. The polymeric esters can be blended with one or more In accordance with this invention, polyurethane foams polyols before reaction with the polyisocyanate to vary are prepared by mixing and reacting the following basic the frequency of OH groups in the polymers being used ingredients: a linear polymeric ester as defined above, an and thereby vary the rigidity or flexibility of the foam to organic polyisocyanate, one or more catalysts, one or be prepared. The only limitation on such blends is that more blowing agents, and asurfactant. Reaction usually the resulting blends contain at least 10% by weight of the acid; 5,6-epoxyhexanoic acid; 2,3-epoxyoctanoic acid; 5,6- epoxyoctanoic acid; 7,8-epoxyoctanoic acid; -2,3-epoxybased on total ingredients.

linear polymeric ester. Exemplary of the polyols which can be used in such blends are: triisopropanolamine, poly (propylene oxide), polyester polyols, [N,N,N',N' tetrakis(2-hydroxypropyl)] ethylene diamine, propylene oxide adducts of sorbitol in which the sorbitol to propyleneoxide molar ratio is from 1:6 to 1:24, propylene oxide adducts of trimethylolpropane in which the .trimethylolpropane to propylene oxide molar ratio is from 1:3 to 1:36, propylene oxide adducts of pentaerythritol in which the pentaerythritol to propylene oxide. molar ratio is from 1:4 to 1:8, etc.

Any organiclpolyisocyanate can be employed in accordance with the instant invention. Most preferably, the isocyanate will be an aromatic polyisocyanate. Examples of the polyisocyanates which can be employed include: polymethylene diisocyanatessuch as ethylene diisocyanate, trimethylene diisocyanate, dodecamethylene diisocyanate, hexarnethylene diisocyanate, tetramethylene diisocyanate, pentamethylene diisocyanate; alkylene diisocyanates such as propylene-1,2-diisocyanate, 2,3-dimethyl tetrai'nethylene diisocyanate, butylene 1,2 diisocyanate, butylene 1,3 diisocyanate; alkylidene diisocyanates such as ethylidene diisocyanate and heptilidene' diisoeyanate; cycloalkylene diisocyanates such as l,4-diisocyantocyclohexane, cyclopentanyl-l,3-diisocyanate;. aromaticpolyisocyanates such as m-phenyllene diisocyanate, p-phenylene diisocyanate, l-methylphenyl- 2,4-diisocyanate, naphthalene-1,4-diisocyanate, naphthalene-1,5-diisocyanate, 0,0- toluene diisocyanate, diphenyl-4,4'-diisocyanate, benzenel,2',4-triisocyanate,. xylylene 1,4 diisocyanate, xylylene- 1,3 -diisocyanate, 4,4 -diphenylenemethane diisocyanate, 1chlorophenyl-2,4-diisocyanate, 4,4-diphe nylene propane diisocyanate; and aliphatic-aromaticdiisocyanates such as methylene bis(4-phenyl)'diisocyana-te, phcnylethylene diisocyanate, polymethylene' polyphenylisocyanate, etc. Theoretically, there should be suflicient isocyanategroups present to react with all of the OH groups of the polymeric ester. In practice, however, there can be considerable variation in the ratio of the two reactants Normally one wouldnot use a great excess of polyisocyanate since it is by far the more expensive reactant. An excess of polymeric ester over polyisocyanate can, and many times is used.

The catalyst used in the process of this invention gen-- erally comprises a mixture of a tertiary amine such as triethylenediamine, tetra-methylbutanediamine, triethylamine, triethanolamine, N-methylmorpholine, N,N'-diethylpiperazi'ne, N,N-dimethylhexahydroaniline, tribenzylamine, N,N dirnethylbenzylamine, etc., with a metal compound such as stannous o'ctoate, zincoctoate; dibutyl tin dilaurate, ferric acetylacetonate, etc. While a mixed catalyst is generally used, it is to be understood that the process can be carried out with any ofthe above-mentioned catalysts used singly- The amount. of catalyst can be varied over a wide range, but in general, the tertiary amines will be used in amounts of from about 0.1% to about 1.0%, by weight, and the metal compounds in an amount of from about 0.1%- to about 1.0%, by weight,

Any of the conventional blowing agentsfor polyurethane foams can be used in accordance with the procedure of this invention. The specific blowing agent used will depend upon the desired utility of the foam. The conventional, and probably the most widely used, blowing. agent is water. The water reacts with the iso-- cyanate groups to form substituted urealinkages, thus. generating carbon dioxide which actually does the blowing'. In another category are the low boiling liquid blowing. agents such as pen'tane, isobutylene, trichlorofluoromethane, dichlorodifiuoromethane, dichlorotetrafluoroethane, etc. Here blowing is attained through vaporization of the liquid by the heat of reaction. A combination of both water and a low boiling liquid can also be used to blow the foams. The use of halogenated hydrocarbon low-boiling liquids are particularly advan- Any surfactant, i.e., emulsifier, which is inert to the reaction, can be used in the process of this invention. Exemplary of the surfactants that can be used are dioctylsodiurn sulfosuccinatc, water-soluble polyethylene ethers of fatty acids, silicone surfactants, etc. Most preferred ,are the ,nonionic silicone surfactants. The concentration of surfactant controls the size and uniformity of cells in--thc foam since it reduces the surface tension of the gas bubble during the foaming process and will usually be from about 0.1% to aboutf1.0%, by weight based on total ingredients.

As mentioned above, there are severalconventional methods used in the preparation of polyurethane foams. These methods fall into three general'categories:

(1) The full prepolymer meth0d.In this method, the polymeric ester is prereactedwith an excess of polyisocyanate; normally a 10% excessv of polyisocyanate is maintained. To form the foam, a mixture of blowing agent, surfactant, and catalyst. (called activator solution in trade jargon) is: mixed with the prepolymer. The most diflicult point in this, as in most methods of preparation, is the balancing of the. foaming and crosslinking reactions so that by the time the foam has reached its full height it will be strong enough to retain the gas generated.-

(2) Quasi-prepolymer method-Here, a portion of the polymeric ester is reacted with all of the polyisocyanate so as to maintain an NCO/OH (molar ratio) of from about 4 to about 6. To form the foam, the quasi-prepol-ymer is mixed with the remainder of the polymeric ester, a surfactant and catalyst.- The required blowing agent. can be added to the quasi-prepolymer, the re-' mainder of the polymeric ester or it can be added separately, depending on which blowing agent is used. If water is used, it can be added to the remainder of the polymeric ester or separately. If a low boiling liquid. is used, it can be added to the quasi-prepolymer, the remainder of the polymeric ester or it can be separately added.

(3) The one-shot method.-This, as" the name implies, consists of mixing all the components at once and allowing them to react. In practice, the number of components is usually reduced by mixing nonreactive ones in advance.

The froth" process is adaptable to all the above In the froth process, all the ingredients for methods. the foam are mixed in a chamber (mixing head) under pressure. By means ofa pressure relief valve, the mixture is ejected to the atmosphere where it immediately expands to form a froth. This froth. is stable enough to stand by itself until the crosslinking reactions have been completed. During the cross-linking, the froth usually expands further.

As stated above, the foams of this invention cari-v be prepared by any of the conventionalemethods- In addition, it is to be noted that the foams can be produced in various forms, as. slab stock, foamed. in place to fill voids (e.g., truck wall insulation), sprayed directly onto a surface to which the foam will adhere, etc. Depending on the methods and ingredients used, the polyurethane foams can have many dilferent properties and utilities as, for example, rigid urethane foams can be prepared as lightweight structural. materials .with many useful insulation and acoustical properties.

. The following examples will bctterillu strate the nature of this invention. However, it is to be understood that epoxystearic acid), a polyisocyanate and a nonionic silicone surfactant were blended with an electric stirrer for 2 minutes. Then water and an amine catalyst were rapidly added and each mixture stirred at high speed for 10 seconds. Each mixture was then poured into a mold where it formed a rigid foam. Each foam was allowed to cure for 24 hours at room temperature before testing its physical properties. The amounts of ingredients used (parts by weight) in the preparation of each foam and the density, compressive strength and tensile strength of the resulting foams are tabulated below.

Examples Ingredients Epichlorohydrin-terminated ply(9,10-epoxystearic aci 1 100 100 Toluene diisocyanate (80:20 mixture of 2,4 to ,6-

toluene diisocyanate) 61. 5 0 Polymethylene polyphenylisocyanute (equivalent weight 133.8) 0 100 Noniontc silicone surfactant 0. 6 0. 6 Water 2. 9 2. 9 N.N,N,N-tetramethyl-1.3-butanediamine 0. 6 0 Triethylenediamine 0 0. 6

PROPERTIES Density, lbs/cu. ft 2. 8 17. 7 Compressive strength deflection), p.s.i. 16 255 Tensile strength, p.s.i 30 203. 5 Volume changefl percent 0. 5

1 Acid number 0.3 and equivalent weight 249.8. 2 Percentage volume change over a period of one week at a. temperature of 100 C. and 100% relative humidity.

Each foam was composed of uniform closed cells. The foam of Example 1 could be used in the manufacture of toys. The foam of Example 2 could be used in the manufacture of building panels.

Examples 3 and 4 In these examples, rigid foams were prepared from different epichlorohydrin terminated poly(9,10 epoxystearic acids) by the following method. In each example, the epichlorohydrin-terminated poly (9,10-epoxystearic acid), blowing agent, catalyst and surfactant were blended for 2 minutes. Then the toluene diisocyanate was added and each mixture was stirred at high speed for 10 seconds. Each mixture was then poured into a mold where it formed a rigid foam. Each foam was allowed to cure for 24 hours at room temperature before testing its physical properties. The amounts of ingredients used (parts by weight) in the preparation of veach foam and the density, compressive strength and tensile strength of the resulting foams are tabulated below. i

1 Acid number 0.3 and equivalent weight 244.8. 1 Acid number 0.3 and equivalent weight 249.8. 9 See Examples 1 and 2.

Each foam was light tan in color and composed of closed uniform cells. The foam of Example 3 could be Example 4 could be used for thermal and shock in- (80:20 mixture of 2,4 to 2,6-toluene diisocyanate) and sulation.

Example 5 This example demonstrates the preparation of a semirigid polyurethane foam using a blend of an epichlorohydrin-terminated poly(9,10-epoxystearic acid) with [N, N,N',N-tetrakis(2 hydroxypropyl) ]ethylenediamine. A mixture was prepared by blending together 50 parts of an epichlorohydrin-terminated poly(9,10-epoxystearic acid) having an acid number of 0.2 and an equivalent weight of 250.2, and 50 parts of N,N,N',N'-tetrakis(2-,

hydroxypropyl)ethylenediamine having an equivalent weight of 73.1, 20 parts of trichlorofluoromethane, 1.25

parts of N,N,N,N-tetramethyl-1,3-butane diamine and 0.75 part of a nonionic silicone surfactant. To this mixture was rapidly added 62.5 parts of toluene diisocyanate the entire mixture stirred at high speed for 10 seconds. The mixture was then poured into a mold where it formed a semi-rigid foam. After curing for 24 hours at room temperature, the foam was found to have a density of 1.7 lbs/cu. ft., a compressive strength (10% deflection) of 31.2 p.s.i., a tensile strength of 28 p.s.i. and 0% volume change under the conditions described in Examples 1 and 2. The foam was light tan in color and composed of closed uniform cells.

Example 6 This example demonstrates the preparation of a rigid foam using a froth-foaming machine. The machine used had a maximum capacity of 4 lbs/min. and was adapted to deliver three separate streams of ingredients to a mixing head maintained at the pressure of 60 p.s.i.g. In the first stream, 100 parts of an epichlorohydrin-terminated poly(9,10-epoxystearic acid) having an acid number of 0.5 and an equivalent weight of 249.8 and containing one part of a nonionic silicone surfactant and 0.8 part of N, N,N,N'-tetramethyl --1,3 butane diamine were metered to the mixing head at a temperature of 49' C. In the second stream, 22 parts of dichlorotetrafiuoroethane were metered to the mixing head. The third stream carried 36.8 parts of toluene diisocyanate (:20 mixture of 2,4

to 2,6-toluene diisocyanate) to the mixing head. The mixture was rapidly stirred by an air driven rotor in the mixing head and then ejected into a mold as a froth. The froth was expanded and hardened to a rigid foam. After curing for 24 hours, the foam was tested and found to have a density of 3.6 lbs./cu. ft., a compressive strength (10% deflection) of 28.8 p.s.i. and a tensile strength of 19 p.s.i. The foam was composed of closed uniform cells and could be used for thermal and shock insulation.

Example 7 This example illustrates the preparation of a rigid foam by the quasi-prepolymer method. A quasi-prepolymer with a calculated NCO/OH of 5.5 was prepared by heating and stirring 20 parts of a propylene oxide-terminated po1y(9,10-epoxystearic acid) having an acid number of 1.6 and an equivalent weight of 302.3 with 31.8 parts of toluene diisocyanate (80:20- mixture of 2,4 to 2,6-toluene diisocyanate) for one hour. When the thus-prepared quasi-prepolymer cooled to room temperature, 25 parts of trichlorofiuoromethane was added with stirring. This quasi-prepolymer mixture containing the halogenated blowing agent was stable and could be stored for long periods of time. A rigid foam was prepared from the quasi-prepolymer by rapidly adding to the mixture an additional 80 parts of the propylene oxideterminated poly(9,10-epoxystearic acid) described above, 1.0 part of N,N,N',N-tetramethyl-1,3-butane diamine and 0.6 part of a nonionic silicone surfactant. The resulting mixture was stirred at high speed for 10 seconds and then poured into a mold. After allowing the thuscomposed of mostly'open cells for shock insulation. e

7 formed foam to cure for 24 hours, it was tested and found to have a density of 15.7 lbs/cu. ft. The foam was composed of closed uniform cells and could be used in the manufacture of building panels.

Example 8 and one part of a nonionic siliconesurfactantwereadded with stirring. This quasi-pr'epolymer mixture was stable and could be stored for long periods of time. A rigid (foam was prepared from the quasi-prepolyrn'er by rapidly 7 adding it to an additional 47.8 parts" of the epichlorohydrin-terminated poly(9,-l-epoxy stearic acid) described above, 24.6 parts'of the triisopropanolamine described above and 1.75 parts'of triet'hylene diamine. The resulting mixture was stirred at high speed for seconds and then poured into a mold. After allowing it"to cure for 24 hours, it..was tested and found to have a density of 2.7 lbs/cu. ft., a compressive strength (10% deflection) of 29.1 p.s.i. and a tensile strenght of 42.6'p.s.i}

Example 9 In this example a foam .wasfprepared from a nonterminated poly(9',10-epoxyste'aric acid). The following,

amounts of ingredients were blended -f0r2 minutes:

. v. I I Parts Poly(9,'l0-epoxystearic acid) 100' Nonionic silicone surfactant 1.1 Di-bu'tyltin dilaurate .10 Triethylamine 13.1 Alkyl phenoxy poly(oxyethylene ethanol) 4.4 Water 6.8

Acid number 75.3, oxiran e-oxygeu"1.84%"by weight and equivalent weight 286.5. i

To the'v resulting mixture was added 91.2 parts of toluene diisoeyanate and'the' entire mixture stirred at high speed for 10 seconds. The mixture was then poured into a mold where it formed a rigid foam. The resulting foam had 1 a density of 7.0 lbs./cu. ft., was light tan incolor and The'foam could be used Ema. 10

A'rigid foam was prepared from a propylene oxide terminated poly( 10,11-epoxyundecanoic acid) having an acid number of 1.5, an oxirane-oxygen content of 0.2%

by weight and an ester number of 216 by the following method. A mixture was prepared byblending together 100 parts, of the end terminated poly(10,1l-epoxyundecanoic acid), 91.5 parts of toluene diisocyanate (80:20

Example 11 A rigid 'foam'was prepared from the propylene oxide terminated poly(10,11-epoxyundecanoic acid) described in Example 10. The end terminated po1y(10,11-epoxyundecanoic' acid) blowing agent, catalyst and surfactant were blended with an electric stirer for 2 minutes. Then the toluene diisocyanate was added, and the mixture was stirred at high speed for 10 seconds. The mixture was then poured into a mold where it formed a rigid foam. The foam was allowed to cure for 24 hours at room temperature before testing its physical P operties. The amounts of ingredients used (partsby weight) in the, preparation of the foam and the density, compressive strength and tensile strength of'the resulitng foam arev tabulated below. p v

Ingredients: 3

. Propylene oxide terminated "poly(1 0 ,11-epoxyundecanoic acid) 100 Trichlorofluoromethane 25 N,N,'N,N'-tetramethyl-1,3-butanediamine 1.0 .Nonionic silicone surfactant 0.6

Toluene diisocyanate (80:20 mixture of 2,4- to 2,6-toluene diisocyanate)? 47.2

Properties;

Density, lbs./cu. ft 5.2 Compressive strength (10% deflection), p.s.i. 18.5 Tensile strength, p.s.i 25

The foam was light. tan in-color and composed of closed uniform cells. It could, he used for thermal and shockinsulation This example illustrates the-preparation of a rigid foam by the full prepolymer method. A full prepolymer with a calculated free isocyanate function of 9.5% by weight was prepared by reacting with stirring 100 parts of epichlorohydrinterminated poly(9',l0-epoxystearic acid) having an acid number of 5.9 and an equivalent weight of '310 with-5315 parts of toluene diisocyanate (80:20 mixture of 2,4- to 2,6-tolu'ene diiso'cyanate) at a temperature of 3537 C. A rigid foam was prepared fromthe full prepolymer by rapidly adding a mixture of 2.9 parts of water, 0.25 part'triethylene diamine, 0.5 part of nonionic silicone surfactant and'stirring at high speed for 5 seconds. The mixture was then poured into a mold where it formed-a rigid foam. After curing for 24 hours at room temperature, the foam was tested and found to have a density of 5.8 lbs/cu. ft. It was light tan in color, had small closed cells and did not change in volume on humid aging. The foam could be used in the manufacture of toys. r

This application is a continuation-in-part of my copending application Serial No. 141,020, filed September 27, 1961.

What I claim and desire to protect by Letters Patent is:

mixture of 2,4- to 2,6-toluene diisocyanate) and 0.6 part 5 in which R is a substituentof the group consisting of of a nonionic silicone surfactant and stirring for 2 minutes. Then 4.8 parts of water and 0.6 part of triethylenediamine were rapidly added and the entire mixture stirred at high speed for 10 seconds. The mixture was then poured hydrogen and alkyl radicals; n is a whole number from 0 to 20, inclusive; x is at least 1; W is a substituent of the group consisting of hydrogen, hydroxyalkylradicals and halohydroxyalkyl radicals; and B is a substituent of the into a mold where it formed a rigid foam. After curing group consisting offor 24 hours at room temperature, the foamwas found to have a density of 1.7 lbs./cu. ft. a compressive strength (10% deflection) of 13 p.s.i.- and a tensile strength of 20 p.s.i. The foam was light tan in color and composed of closed uniform cells. I r

R-oH- -criradicals, a-crr-cnradicals, and

, R 0 11-0 11- radicals Parts 9 in which R hasvthe same significance as set forth above, and X is a halogen substituent.

2. A polyurethane foam comprising the foamed reactionproduct of an organic polyisocyanate, a' blowing agent and a polyol containing at least 25% by weight of a linear polymeric ester having the general formula:

in which R is a substituent of the group consisting of hydrogen and alkyl radicals; n is a whole number from to 20, inclusive; x is at least 1; and W is a substituent of the group consisting of hydrogen, hydroxyalkyl radicals and halohydroxyalkyl radicals.

3. The product of claim 2 wherein the polyol is epichlorohydrin-terminated poly(9,10-epoxystearic acid).

4. The product of claim 2 wherein the polyol is propylene oxide-terminated poly(9,epoxystearic acid).

5. The product of claim 2 wherein the polyol is propylene oxide terminated poly(10,11 epoxyundecanoic acid).

5 of a linear polymeric ester having the general formula:

in which R is a substituent of the group consisting of hydrogen and alkyl radicals; n is a whole number from 0 v to 20, inclusive; x is at least 1; W is a substituent of the group consisting of hydrogen, hydroxyalkyl radicals and halohydroxyalkyl radicals; and B is a substituent of the group consisting of RCHCH radicals, R-CH-CH- radicals, and

R-CH--CH radicals in which R has the same significance as set forth above,

6. The product of claim 2 wherein the polyol is a and X is a halogen substituent.

mixture of epichlorohydrin-terminated poly(9,10-epoxystearic acid) and [N,N,N',N'-tetrakis(2-hydroxypropyl)] ethylenediamine.

7. A rigid polyurethane foam comprising the foamed reaction product of a toluene diisocyanate, epichlorohy- 3 112 325 11/63 Murata et all 260 348 drin-terminated poly(9,10-epoxystearic acid) and a lowboiling halogenated hydrocarbon liquid, said foam having a closed cell content of at least 8. In the process. of preparing a polyurethane foam References Cited by the Examiner UNITED' STATES PATENTS 3,075,926 1/36 Stewart et a1. 2602.5

LEON J. BERCOVIT Z, Primary Examiner.

DONALD E. CZAJA, Examiner.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,184,420 May 18, 1965 Karl Bracl It. is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Column 1, lines 50 to 55, the formula should appear as shown below instead of as in the patent:

column 8, lines 60 to 64, the formula should appear as shown belov instead of as in the patent:

H [CH COW OH 2 n T i: (IIH FH R R column 9, lines 12 to 16, the formula should appear as shown below instead of as in the patent:

8 I? ll R-CH-CH- [CH CO CH [CH C-O CH [CH COW 2 n 2 n 2 n OH OH column 10, lines 6 to 10, the formula should appear as shown below instead of as in the patent:

Signed and sealed this 28th day of December 1965.

(SEAL) Attest:

EDWARD J BRENNER Commissioner of Patents T Re EC i If Wf 50 .g Wn

1 t S5 B6 NT Rt E A 

1. A POLYURETHANE FOAM COMPRISING THE FOAMED REACTION PRODUCT OF AN ORGANIC POLYISOCYANATE, A BLOWING AGENT AND A POLYOL CONTAINING AT LEST 10% BY WEIGHT OF A LINEAR POLYMERIC ESTER HAVING THE GENERAL FORMULA: 